CONFORMATION OF HORSES

Agriscience 334

Equine Science

#8893-B

TEKS: 119.66 (c)(2)(B)

Introduction

Conformation plays an important role in the ability of a horse to perform.

Conformation refers to the structure or outline of an animal as determined by the arrangement of its parts.

Horses differ in conformation, which affects how well they can perform in different events.

When choosing a horse, one should be able to recognize standard conformation and conformation faults and match the purpose of the horse with the conformation that is best suited for that purpose.

Mechanics of EvaluationWhen evaluating a horse, one should follow a few simple procedures:

• Observe the horse from a distance;

• Check out how the horse moves and its action;

• Move in close and inspect for blemishes and abnormalities;

• View the horse from different directions (front, rear, and sides).

• Develop a logical systematic procedure that is consistent and effective.

General InformationIn order to discuss conformation standards, one should be familiar with the nomenclature used in describing horses.

Identifying the external anatomy, skeleton, and muscles is important to the evaluation of horses.

General Appearance or Quality

Quality refers to the attractiveness of a horse and is based on several factors.

Photo by Bill Tarpenning courtesy of USDA Photography Center.

Head

The exact shape of a horse’s head varies depending upon the breed.

The shape of the head affects vision and balance.

Photo by Bill Tarpenning courtesy of USDA Photography Center.

The head should be triangular in shape, when viewed from the front and sides.

From the side, the jaws should be deep and the head should taper to a smaller-sized muzzle.

A head that is too large restricts the horse’s field of vision.

The head should not be too long or too short; instead, the head should be in proportion with the neck and the body.

It is important that sufficient length exists between the eyes and muzzle of the horse.

This is the location of the turbinates, which heat and cool the inhaled air before it enters the lungs.

A head that is too big can shift the horse’s center of gravity forward.

A horse with an extremely long or narrow head has a large blind spot on the ground in front of it; the longer head blocks the view.

The shape of the face from the side varies among breeds.

Arabian horses have the famous dish-shaped face, which actually improves vision to the front.

The Roman nose or convex shape impairs frontal vision.

Most people prefer a straight profile face.

The upper and lower teeth must meet evenly, otherwise the horse will have problems eating.

An upper jaw that is too long is called a parrot mouth.

A short upper jaw is an undershot jaw.

These faults with the upper jaw are heritable and should be avoided.

The eyes of the horse should be large, clear, and set on the sides of the head with good width between the eyes.

If eyes are wide set on the side of the head, the horse should have almost 360 field of vision with a few blind spots.

A “pig-eyed” horse has small eyes set too far back in the head.

The ears of the horse should be neat and alert.

The ears should curve around and taper to a fine point.

The ears should not be set too far apart, set too close together, or be too droopy.

Neck

The head and neck are mechanisms for balance in a horse.

An ideal neck is long and trim, with a clean throatlatch.

A clean throatlatch means that enough space occurs between the jaw, throat, and neck, allowing the horse to move its head and neck without difficulty.

A horse with a wasty (thick and fat) throatlatch may have difficulty breathing.

The neck of a horse should blend smoothly into the shoulders and tie high into the throatlatch.

Judges do not like a neck that is too low or inserts too deep into the chest.

BalanceA well-balanced horse is one whose body parts all blend together to form a pleasing picture.

When evaluating balance, the horse is divided into three equal regions as it is viewed from the side.

Starting at the front of the horse, the first region is the shoulder (A).

We define the length of the shoulder as the length from the point of the shoulder to an imaginary line that is perpendicular to the withers.

The second region is the back (B).

The length of the back is the distance from the base of the withers to the start of the croup.

The third area is the hip (C).

The length of the hip extends from the flank to the point of the hip.

In a well-balanced horse, these three areas equal each other in length.

Additionally, the horse should have a long, sloping shoulder (D); a short, strong back in relation to the underline of the body; and a long, comparatively level croup (E).

Judges also look at balance from the withers to the ground, going from top to bottom.

The measures dividing this line are called “depth of heart girth” and “length of leg.”

Ideally, the distance from the withers to the girth (F), called heart girth, is approximately equal to the distance from the girth to the ground (G).

A judge would like the horse to be level from the withers to the croup (known as the topline).

Horses that are higher at the withers than at the croup are “uphill” horses, while those horses higher at the croup than at the withers are “downhill” horses.

Shoulder

A long, sloping shoulder is ideal.

Look at the scapula to evaluate the shoulder.

Steep shoulders are shoulders that are too far forward on the horse’s body.

Steep shoulders give the appearance of long shoulders, but the shoulders are actually short and have a steep angle.

One of the main areas that absorbs concussion in the horse’s body is the juncture between the shoulder and the arm.

With a steep angle, increased wear and tear on the leg occurs due to trauma.

Horses with a steep arm angle are prone to the types of lameness caused by poor concussion absorption.

A horse with steep shoulders is rough to ride because the concussion travels all the way up the horse and ends up in the rider.

A horse with good shoulder angulation and an adequately long shoulder have a longer, smoother stride (“good mover”).

Back

Horses should have short, strong backs as compared to long, tapering underlines.

Horses with long backs are not well-balanced; the long back breaks up the smooth line of the top line.

The back of a horse should have adequate muscling to be able to support the rider.

The loin is only supported by the vertebral column; it should be short from front to rear, wide across, smooth, and convex, with a firm, elastic consistency.

Without adequate muscling, a horse is inclined to become swayback (a back that sags).

Too much length in the back can affect the gait, giving the hindquarters a rolling motion.

A horse with a convex back, or “roach back,” may cause the lower legs to interfere.

A roach back is often a sign of spinal misalignment and it lacks flexibility.

A roach backed horse exhibits a short stride and tends to overreach.

Hip

Horses should have long hips in relation to other areas of their bodies.

The hindquarters contain the driving force of the horse’s locomotion.

Muscling is evaluated by looking at the length and definition of the muscle that passes over the croup.

The horse should also have well-developed stifle muscles that extend down toward the hock.

The croup angle influences the motion of the hind legs.

A relatively flat croup encourages a long, flowing stride.

A horse with a steep croup may have short strides.

Croup length affects stride length.

Horses with short croups have short, uneven strides.

Horses with long croups have long, flowing strides.

Heart Girth

Ideally, a horse should be deep in the heart girth and have large circumference of the heart girth.

This allows the horse to have enough space to hold the vital organs, which improves the horse’s performance.

Structural Correctness and Travel

Skeletal structure controls conformation; the feet and legs are crucial parts of conformation.

Performance horses are athletes; they must have straight legs.

Straightness of legs refers to the alignment of the column of bones in the front and rear legs.

Knees and hocks should be close to the ground for the horse to cover ground quickly and easily.

Arm

The arm (humerus) should be short in comparison to the length of the shoulder.

An arm that is too long places the foreleg way too far under the body and the horse will carry too much weight on the front part of its body.

An arm that is too short cuts the horse’s stride length.

Forearm

The forearm should be long and have muscles that attach deep into the knee.

This will promote a long stride, especially if the horse has a comparatively short cannon bone.

Knees

The horse should have wide, flat, and smooth knees.

With a large knee, the horse will have more surface area for support, thus less stress per unit of area.

The radius and cannon bones should be centered with the knee.

A bench knee, or offset knee, is a condition that exists when the cannon bones are set to the outside of the knee bone.

“Open knee” occurs when the knee bone is too small; this condition puts additional concussion or stress on the knee bone.

“Chopped knee” occurs when the cannon bone is too small and is set too far under the knee from the side.

“Tied Knee,” the result of tendons that are too small, gives the cannon area a constricted appearance and can cause bowed tendons if the horse is stressed.

Hocks

A good hock is deep, wide, strong, and well-defined.

The angle, or set, of the hock is important.

Hocks that are excessively straight or hocks that have too much angle cause unsound conditions.

Cannon Bones

The cannon bones should be short (compared to the forearm).

This will allow the knees and hocks to remain closer to the ground, which will increase stability and create a longer stride.

The cannon bones should be refined (see tendons clearly articulated) and have a “clean appearance.”

The cannon bone is round; but, it should appear flat, when viewed from the side, due to the tendons behind it.

Rear cannon bones can be larger than the front cannon bones.

Photo by Bill Tarpenning courtesy of USDA Photography Center.

Pasterns

The pasterns should be moderately long and sloping.

Pasterns that are too long cause the fetlocks to drop too much, which puts tremendous strain on the fetlocks.

This can promote the development of bowed tendons.

Pasterns that are too short cause the horse to be a rough ride.

The pastern angle and the shoulder angle should correspond to each other.

Feet

Horses should have large feet in proportion to their bodies.

The feet absorb a lot of concussion; if they are too small, the feet experience more wear and tear.

It is not likely that you will see a horse with feet that are too big.

Some horse breeders erroneously selected for horses with small feet.

Many horses with little feet develop lameness in the feet.

Structural Conformation Defects and Resulting Travel

The horse should be viewed from the front, side, and rear when evaluating structural conformation and travel.

When viewed from the front, the forelegs should be straight.

Lines drawn from the points of each shoulder down to the ground should be parallel and bisect the legs equally.

With the side view, the line should bisect the foreleg and touch the bulb of the heel.

A side view of the hind leg should allow you to draw a line from the point of the buttocks downward; the line should touch the back of the hock, go parallel to the cannon, and touch the ground three to four inches behind the heel.

With a rear viewpoint, a line starting at the point of the buttocks should bisect the hocks, cannons, and heels.

Conformation determines the horse’s way of traveling.

To be useful, a horse needs to be able to move well, and that movement needs to be straight and true.

The horse’s strides need to be free flowing and have sufficient snap and flexion.

However, an extreme amount of knee and hock action should be discriminated against.

Front View Defects

When viewing the animal from the front, remember that the forelegs should be straight and normal feet move in a straight line.

Bench Kneed

Bench kneed, or offset knees, as discussed before, is a major fault.

The cannon bones reside outside (lateral) of the knee and augment stress on the inside (medial) of the knee.

Base-wide

With this defect, there is more width between the center of the hooves than the center of the shoulder points. Stress on the knee occurs with this defect, along with interference of the opposite foreleg when traveling.

In travel with base-wide defect, the foot breaks over the center of the hoof, wings inward, and travels back outward, landing on the inside of the hoof.

Base-narrow

The foot of a horse that is base-narrow may break over either the center of the toe or the outside of the toe.

Due to too much concussion, the outside of the leg may become unsound in a horse that is base-narrow.

Toes Out or Splay-footed

A horse with straight legs down to the knee will have a “toed-out” appearance if the cannon bone is rotated toward the outside.

With a splay-footed horse, the foot breaks over the inside of the toe, wings inward, and goes back outward, landing on the inside of the hoof, possibly causing damage to the inside of the hoof and foreleg.

Pigeon-toed or Toe Narrow

A pigeon-toed, or toe narrow, horse incurs more stress on the fetlock area.

This defect normally shifts the horse’s center of gravity forward.

If pigeon-toed, the horse will paddle (throw its feet outward as it picks them up).

The outside leg may be prone to lameness.

Bowlegged

Horses that are bowlegged are wider at the knees than any other part of the foreleg.

This causes too much strain on their knees and will reduce mobility.

Knock-kneed

A horse that has knees closer together than any other part of the foreleg is knock-kneed and may have feet that interfere with one another when the horse is moving.

Side View Defects of Front Legs

When viewing horse from the side, remember that the line for the front leg should bisect the foreleg and touch the bulb of the heel.

Buck Knees

“Over at the knee” and “knee sprung are other common names for buck knees, which extend forward of a line bisecting the foreleg from the side.

Slight buck knees may not cause many problems, but the extreme defect places strain on the flexor tendons and sesamoid bone, when in motion, and can cause bowed tendons and sesamoiditis.

Calf-kneed

When the knees extend behind lines that bisect the forelegs a horse is calf-kneed.

As one of the worst imperfections in the forelegs, calf-knees cause too much strain on the knees.

Camped Out

Camped out refers to a horse whose forelegs are not set squarely under, but extended forward; the result is a horse that has difficulty moving its forequarters.

This condition is often seen in horses that are foundered or have navicular disease.

Due to pain, they try to place weight on the back part of the feet, with the legs at an angle.

Camped Under

Camped under refers to a condition in which the forelegs are set too far back under the horse.

This causes too much weight on the forehand, resulting in shorter strides and stumbling.

Side View Defects of Hind Legs

When viewing the hind legs from the side you should be able to draw a line from the point of the buttocks downward; the line should touch the back of the hock, go parallel to the cannon, and touch the ground three to four inches behind the heel.

Sickle-hocked

“Sickle-hocked” horses have too much angle in the hocks.

Sickle-hocked horses will have a shorter stride than horses with a normal angle and are more prone to unsound conditions, such as “curb” (an enlarged ligament), bone spavins, bog spavins, and thoroughpins.

Post-legged

“Post-legged” horses do not have enough angle at their hocks.

The post-legged condition severely limits the flexibility of the hind leg movement and increases the incidence of injury (stiffness, bog spavins, lameness) due to the extra stress placed on the hock.

Camped-out and Camped-under

The camped-out or camped-under conditions that occur in the forelegs can also occur in the hind legs.

The camped-out condition, which has the hind legs set behind the horse, makes it difficult for the horse to get its legs under it and the horse cannot seem to collect itself.

The legs tend to jab the ground, and the horse cannot lift its body well for jumping.

A horse with its hind legs camped-under has legs that set in front of the ideal line.

Rear View Defects

With a rear viewpoint, a line starting at the point of the buttocks should bisect the hocks, cannons, and heels.

Base-wide

The base-wide condition is rare in horses; the legs extend outside of the line from the buttocks.

Base-narrow

In the base-narrow condition, legs are inside of the line from the buttocks, which is a common fault of horses.

The base-narrow condition can be caused by too much outer gaskin muscle and result in increased stress and injury to the outside of the hind leg.

Cow-hocked

If a horse is cow-hocked, its hocks turn inward to the inside of the ideal line from the buttock and the horse may stand base-wide and toe-wide.

A cow-hocked horse places excess stress on the inside of the leg, increasing the incidence of bone spavin.

The hindquarters lack power and movement because legs move outward instead of forward.

Bow-legged

Bow-legged, or bandy-legged, is a condition in which the hocks point outward from the ideal line.

With the bowlegged condition, the hocks tend to rotate with each stride, placing pressure on the hock joint.

The hindquarters are weak and the horse tires easily.

Muscling

Muscles should be long, smooth, and well-defined.

Photo by Bill Tarpenning courtesy of USDA Photography Center.

Muscle evaluation:

• Forearms – powerful muscles that tie deeply into the knee;

• Sufficient width between the front legs;

• Chest muscles (pectoral) need to have bulge and quality – long and deep tying;

• Back and loin muscling is imperative to support the rider’s weight;

• Coupling (connection of loin with hindquarters) should be intensely muscled and wide to help support the loin; it should also be short and strong;

• The hindquarters are the source of power for the horse; they should be broad and well-muscled.

Different breeds of horses exhibit various degrees of muscling.

The degree of muscling is also correlated with the events in which the horses compete.

Photo by Bill Tarpenning courtesy of USDA Photography Center.

Horses used for events that require power (pulling, working cattle, reining) should have larger, bulkier muscles.

Photo courtesy of USDA Photography Center.

Horses used for speed events (sprinting, barrel racing, middle and long distance racing, eventing, and jumping) should have long, slim muscles.

Photo by Bill Tarpenning courtesy of USDA Photography Center.

Width through the stifle and width through the hips indicate how heavily muscled a horse is through the hindquarters.

A more heavily muscled horse is wider at the stifle than at the hip.

Thigh muscles should be powerful, wide, and deep.

Stifle muscles should be long, extending into the gaskin.

The gaskin muscles should be bulky and should be apparent on both the inside and outside of the gaskin.

Summary

When judging horses, take all factors into consideration.

The best individual horse will be the one that has balance, structural correctness, muscling, travel, and quality.

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